Process and machine for variably cutting roofing slate



J. H. EMACK PROCESS AND MACHINE FOR VARIABLY CUTTING ROOFINU SLATE Filed Oct. 9. 1922 Feb. 2 1926.

y WITNESS.

Patented Feb. 2, 1926.

UNITED STATES JAMES H. EMACK, OF PHILADELPHIA, PENNSYLVANIA.

PROCESS AND MACHINE FOR VARIABLY CUTTING ROOFING SLA'IE.

Application filed October 9, 1922.` Serial No. 593,341.

To all whom t may concern:

Be it known that I, JAMES II. EMAGK, a citizen of the United States, residing at Philadelphia, county of Philadelphia, and State of Pennsylvania, have invented a new and useful Improvement in Processes and Machines for Variably Cutting Roofing Slate, of which the following is a full, clear, and exact description, reference being` had to the accompanying drawings, which form a partof this specication.

The object of my invention is to so shape slabs or plates of roofing slate that when assembled together to form a roof, they will give to the roof an appearance of antiquity. I accomplish this result by trimming those edges of the slabs that in the finished roof are exposed, in such manner that different slabs of slate will present edges of different contour, the contours being so variable and irregular that the finished roof will present the appearance of having been so worn by long exposure. It is well known to impart to the edges of slate slabs contours diiferent from the more lusual straightcut at right angles to the side edges, as, for example, to make such end edges of curved or pointed form, so that the finished roof will present a uniform pattern. My object, however, is to avoid a pattern and to avoid uniformity and at the same time dispense with the necessity of providing a multiplicity of cutting tools of different shapes. I have attained `my object by means of a single cut ting tool, by means of which I am able not only to obtain a number of different contours for the edges but am able theoretically to secure an infinite variety of contours and practically to obtain so many different contours that there is no perceptible precise reptition of shape in the slates of an entire -roo I accomplish my object by the provision of a tool having cooperating cutting edges considerably longer, and preferably several times longer, than the edge of a slate, such cutting. edges being of irregular broken form, usually notched or pointed at one or more points, and at most or all parts of its length extending in a line that is curved or, if straight, is at an oblique angle to the side edges of the slate; whereby different pieces of slate may be subjected to the action of the tool at different locations along the length thereof.

My invention may be best understood by reference to the accompanying drawings, in which- Fig. l is a face or plan view of a portion of a roof composed of slates the exposed edges of which are cut in accordance with my invention. A

Fig. 2 is a front elevation of the machine.

Fig. 3 is a section on the line 3-3 of Fig.

Fig. 4 is a plan view of the upper blocks of the machine.

Fig. 5 is a vertical cross-section, on a large scale, through all the blocks of the machine. y

Upon the side members a of a stand is mounted a wooden block Above the block 7) is a second block c. The block c is recessed in its bottom face nearits opposite ends and in each recess is mounted a coil spring CZ, which normally holds the block c retracted above the block b. The coil springs Z are guided on rods e, secured in block o. Rods y' extend down from block c through oriiices in block to a foot treadle f hinged to the rear member g of the stand.

Also supported upon the side members a of the stand is a third block 7L, which abuts sidewise against the block Z) and the upper face of which is below the level of the upper face of block l). A. fourth block abutting` laterally against: the block c, is re` cessed similarly to block c and is held a considerable distance above the block h (so that its lower face is normally above the level of the lower face of block c) by means of coil springs c. The coil springs 7': are guided on rods m, which are secured rigidly with block 7L and extend loosely upward through block z' and upon which block z' is slidable.

Dovetailed in the upper inner corner of block o is a clamping and shearing member n. Similarly inserted in the lower inner corner of block c is a clamping member o. Similarly inserted in the lower inner corner of block i is a shearing member p.

In plan view the cooperating edges of the members n, 0 and p extend in an irregular broken line y, as illustrated in Fig. 4. This line may be partly pointed, partly notched, partly straight and partly curved, as illnstrated in Fig. 4. My invention, however, involves no particular form of irregular edge, so long as the variation in departure from a straight line parallel to the direction of longitudinal extension of the blocks is sufficient to provide a multiplicity of overlapping sections having different contours. The length of these edges is necessarily con; siderably greater, and preferably several times greater, than the Width of a slate, so that the slate may be inserted at any point along its length.

In operating the machine, upon release of the foot treadle the block, c is retracted from the block b by springs d, the slate is inserted lengthwise until .its straight edge projects a short distance beyond the members n and o, and the foot treadle is pressed down, coinpressing the springs l and holding the slate securedly clamped. f

By any suitable power means (not shown), the block c' is then depressed quickly independently of c so that the shearing member p strikes the projecting edge of the plate a sharp blow (all parts of the length of such projecting portion` being struck simultaneously), the shearingA members y) and n cooperating to sever the projecting cleanly Without undercut; in other Words, so that the edge of the slate, after severance, extends vertically at right angles to the upper and lower faces thereof. Upon release of the power, the springs lift the block z' to its original position.

The operator Will insert different slabs of slate at different positions along the 1nachine. The possible number of such Lpositions is substantially infinite, so that no tivo finished slabs Will present the same contour of trimmed edge; Figure 1 (containing a number of slabs of slate w assembled as in rooting) giving an imperfect idea of the variety of contours which is obtainable by the use of my invention.

The invention is obviously not confined in its operation to slabs of slate, although as applied to slabs of that material the invention Will probably find its most useful application.

Having now fully described my invention, What I claim and desire to protect by Letters Patent is:

l. rlChe process of manufacturing slabs of slate with edges having an indefinite variety of contours which comprises subjecting theslabs to the action of a cutting tool having a cutting edge of substantially greater length than the Width of the individual slab and of such irregular broken contour that any substantial portion of its length is of different contour from any other substantial portion of its length, and presenting the slabs to the cutting tool :it a variety of lateral positions along the length thereof to produce slabs with trinnnededges having a variety of different contours.

2. The process of manufacturing slabs of slate Which comprises positioning the Slabs successively in diiferent lateral positions with respect to a cutting edge of substantially greater length than the Width of a slab and of irregular brolten contour and subjecting the slabs, so differently positioned, successively to a cutting action so as to produce slabs cach having an irregular edge and with diii'erent slabs having irregular edges of a variety of configurations.

8. A slate trimming machine Whose tool cutting edge is substantially longer than the slate edge to Abe trimmed, said cutting edge having an irregular brolten contour so that any substantial portion of its length .is of different cont-our from any other substantial portion of its length whereby the contour of trimmed edges of different slate slabs may be varied substantially indefinitely With different lateral positionings of the slabs relatively to said cutting edge.

In testimony of which invention, I have hereunto set my hand, at Philadelphia, Pa., on this 5th day of October, 1922.

' JAMES I-I. EMACK. 

